Up to now, you've only had a seven-day cooling off period if the rep turned up unannounced.

This meant that if the firm phoned in advance and persuaded you to let them in, then there was no chance to change your mind if you signed an agreement to buy their kitchen/conservatory/double glazing/orthopaedic bed.

Now the new Doorstep Selling Regulations will cover all visits by sales reps, whether solicited or unsolicited, on deals worth £35 or more.

Doorstep sellers must inform customers in writing of their cancellation rights, the Office of Fair Trading announced.

Susan Marks of Citizens Advice said: "We are delighted that at long last, six years after we lodged our super-complaints with the OFT, people finally have the clear cancellation rights we said were needed.

For far too long doorstep selling has been an area in which unfair trading practices have thrived.

"We hope these new rights will help end public confusion and put a stop to dodgy doorstep sales across a wide range of goods and services, particularly those that exploit vulnerable elderly and disabled consumers."